Coding4Fun - 使用 lock 共用靜態物件 vs 每次新建物件之效能比較

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using System;
using System.CodeDom.Compiler;
using System.Linq;
using System.Reflection;
using System.Threading.Tasks;

namespace JSEval
{
    class Program
    {
        static void Main(string[] args)
        {
            //驗算 EvalLock 與 EvalInstance 結果一致
            var resLock =
                Runner.Expressions.ToDictionary(o => o, o => JSEvaluator.EvalLock(o));
            var resInstance =
                Runner.Expressions.ToDictionary(o => o, o => JSEvaluator.EvalInstance(o));
            var chk = resLock.Where(o => o.Value != resInstance[o.Key]);
            Console.WriteLine($"結果不一致筆數 = {chk.Count()}");
            BenchmarkRunner.Run<Runner>();
        }
    }

    public class Runner
    {
        static Random rnd = new Random(9527);
        public static string[] Expressions =
            Enumerable.Range(1, 8192)
            .Select(o => $"{rnd.Next(100)} + {rnd.Next(100)} //{Guid.NewGuid()}")
            .ToArray();

        [Benchmark]
        public void TestEvalLock()
        {
            Parallel.ForEach(Expressions, e =>
            {
                JSEvaluator.EvalLock(e);
            });
        }
        [Benchmark]
        public void TestEvalRecompile()
        {
            //太慢了，只跑1/128的數量
            Parallel.ForEach(Expressions.Take(8192 / 128), e =>
            {
                JSEvaluator.EvalRecompile(e);
            });
        }
        [Benchmark]
        public void TestEvalInstance()
        {
            Parallel.ForEach(Expressions, e =>
            {
                JSEvaluator.EvalInstance(e);
            });
        }
    }

    public class JSEvaluator
    {
        static Type _jseType = null;
        static object _jse = null;
        static CodeDomProvider provider = CodeDomProvider.CreateProvider("JScript");
        static string jScriptCode = @"class JSEvaluator {  
public function Eval(expr : String) : String { return eval(expr); } 
}";
        static JSEvaluator()
        {
            var compResult = provider.CompileAssemblyFromSource(
                new CompilerParameters { GenerateInMemory = true },
                jScriptCode);
            Assembly asm = compResult.CompiledAssembly;
            _jseType = asm.GetType("JSEvaluator");
            _jse = Activator.CreateInstance(_jseType);
        }

        public static string EvalLock(string expr)
        {
            lock (_jseType)
            {
                return _jseType.InvokeMember("Eval", BindingFlags.InvokeMethod,
                    null, _jse, new object[] { expr }).ToString();
            }
        }

        public static string EvalRecompile(string expr)
        {
            var compResult = provider.CompileAssemblyFromSource(
                new CompilerParameters { GenerateInMemory = true },
                jScriptCode);
            var jseType = compResult.CompiledAssembly.GetType("JSEvaluator");
            var jse = Activator.CreateInstance(jseType);
            return jseType.InvokeMember("Eval", BindingFlags.InvokeMethod,
                null, jse, new object[] { expr }).ToString();
        }

        public static string EvalInstance(string expr)
        {
            var jse = Activator.CreateInstance(_jseType);
            return _jseType.InvokeMember("Eval", BindingFlags.InvokeMethod,
                null, jse, new object[] { expr }).ToString();
        }
    }
}